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Artifi cial neural networks in the recognition of the presence of thyroid disease in patients with atrophic body gastritis

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World Journal of Gastroenterology 2008年第4期14卷 563-568页

作者： Edith Lahner marco Intraligi Massimo Buscema marco Centanni Lucy Vannella Enzo Grossi Bruno Annibale Department of Digestive and Liver Disease University "La Sapienza"2nd Medical SchoolOspedale Sant'AndreaRomeItaly Semeion Research Center Rome Italy Endocrinology Unit Department of Experimental Medicine and PathologyUniversity "La Sapienza"Polo PontinoLatinaItaly Bracco Imaging Spa MilanItaly

AIM: To investigate the role of artifi cial neural networks in predicting the presence of thyroid disease in atrophic body gastritis patients. METHODS: A dataset of 29 input variables of 253 atrophic body gastritis patients was applied to artifi cial neural networks (ANNs) using a data optimisation procedure (standard ANNs,T&T-IS protocol,TWIST protocol). The target variable was the presence of thyroid disease. RESULTS: Standard ANNs obtained a mean accuracy of 64.4% with a sensitivity of 69% and a specifi city of 59.8% in recognizing atrophic body gastritis patients with thyroid disease. The optimization procedures (T&T-IS and TWIST protocol) improved the performance of the recognition task yielding a mean accuracy,sensitivity and specifi city of 74.7% and 75.8%,78.8% and 81.8%,and 70.5% and 69.9%,respectively. The increase of sensitivity of the TWIST protocol was statistically signifi cant compared to T&T-IS. CONCLUSION: This study suggests that artificial neural networks may be taken into consideration as a potential clinical decision-support tool for identifying ABG patients at risk for harbouring an unknown thyroid disease and thus requiring diagnostic work-up of their thyroid status.

关键词： Atrophic body gastritis Thyroid disease Artificial neural networks

Discovering the Long:Current Theories and Trends in Research on the Chinese Dragon

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Frontiers of History in China 2021年第1期16卷 123-142页

作者： marco Meccarelli Department of History University of CatiniaCatinia 95125 Department of History University of MacerataMacerata 62100 Department of History University of UrbinoUrbino 61029Italy

After the 1980s,the world started addressing the challenges posed by economic globalization,and the protection of cultural diversity became a widely discussed ***,China is experiencing problems in defining the relationship between the past and present,as well as that between tradition and *** the 1990s,China’s opening-up policy,the advent of globalization,and an increase in cross-cultural communications strengthened the country’s need to preserve its cultural *** Chinese scholars reflected on the past and examined the potential of archaeological materials,inscriptions,myths,and ancient legends to explain the relationship between tradition and *** birth and evolution of the long龍,or the Chinese dragon,remains at the core of such international *** studies highlighted the necessity of promoting discussions on and demystifying the *** new perspective facilitates a connection between various theories on the origin of the Chinese dragon and the contemporary identity discourse,which has attracted the attention of Chinese *** paper bridges the gap by introducing reliable theories on the origin of the mythical animal and focusing on typology issues,classification,latest debates on the distinction between the long and the dragons of other cultures,and finally,main theories on the visual representation of the Chinese long.

关键词： dragon long loong thunder alligator totem theory mythical animal snake dragon motif

A review of the sentinel prey method as a way of quantifying invertebrate predation under field conditions

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Insect Science 2017年第4期24卷 528-542页

作者： Gabor L. Lovei marco Ferrante Department of Agroecology Flakkebjerg Research Centre Aarhus University Forsgsvej 1 DK-4200 Slagelse Denmark

Sentinel prey can provide a direct, quantitative measure of predation under field conditions. Live sentinel prey provides more realistic data but rarely allows the partitioning of the total predation pressure; artificial prey is less natural but traces left by different predators are identifiable, making it suitable for comparative studies. We reviewed the available evidence of the use of both types of invertebrate sentinel prey. Fifty- seven papers used real prey, usually measuring predation on a focal （often pest） species, with studies overwhelmingly from North America. The median predation was 25.8% d-1. Artificial sentinel prey （45 papers） were used in both temperate and tropical areas, placed more above ground than at ground level. The most commonly used artificial prey imitated a caterpillar. Up to 14 predator groups were identified, registering a median of 8.8% d J predation; half the studies reported only bird predation. Predation on real prey was higher than on artificial ones, but invertebrate predation was not higher than vertebrate predation. Invertertebrate but not vertebrate predation was negatively related to prey size. Predation near the Equator was not higher than at higher latitudes, nor in cultivated than noncultivated habitats. The use of sentinel prey is not yet standardised in terms of prey size, arrangement, exposure period or data reporting. Due to the simplicity and ease of use of the method, such standardisation may increase the usefulness of comparative studies, contributing to the understanding of the importance and level of predation in various habitats worldwide.

关键词： arthropods artificial caterpillar biological control ecosystem service mortality top-down effects

Mapping and ultrastructure of antennal chemosensilla of the wheat bug Eurygaster maura

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Insect Science 2009年第2期16卷 193-203页

作者： Roberto Romani marco Valerio Rossi Stacconi Dipartimento di Scienze Agrarie e Ambientali Facolt& di Agraria Universit& degli Studi di Perugia Perugia Italy

Antennae of the wheat stink bug Eurygaster maura L. （Hemiptera： Scutelleridae） were investigated to elucidate structure and distribution of antennal chemosensilla in females. Five type of sensilla were identified and characterized using a scanning electron microscope （SEM） and a transmission electron microscope （TEM）. Type 1 sensilla are mechanical and contact chemoreceptors with a single apical pore. Types 2 and 3 sensilla are multiporous chemoreceptors both with typical features of olfactory sensilla. Type 4 are multiporous peg-like sensilla, short and with a grooved surface. Type 5 are sensilla coeloconica with a smooth and aporous peg completely inserted in a sub-cuticular chamber. All types are distributed on the two flagellar segments, but we considered only the apical flagellomere in which the largest number of sensilla are located. The most abundant sensilla are type 3, while the less numerous are type 5. All types, except type 2, decreased in number from the tip to the base of the segment. The lower density of sensilla was recorded on the dorsal-internal part of the apical antennomere, while the higher density was recorded on the opposite side （external-ventral）.

关键词： functional anatomy gustatory sensilla Hemiptera olfactory sensilla thermo-hygro receptors

Analysis of jacking forces during pipe jacking in granular materials using particle methods

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Underground Space 2019年第4期4卷 277-288页

作者： Xinbo Ji Pengpeng Ni marco Barla School of Civil Engineering Sun Yat-sen UniversityZhuhai 519082China School of Civil and Environmental Engineering Nanyang Technological UniversitySingapore 639798Singapore The Fifth Engineering Co. Ltd.of ChinaTiesiju Civil Engineering GroupJiujiang 332000China Department of Structural Geotechnical and Building EngineeringPolitecnico di TorinoTurinItaly

Trenchless technology is often used in congested urban areas or river crossings to install underground pipelines to minimize disturbance to surface traffic or other *** jacking is a typical technique applied to jack pipe segments between two working ***,the design of the jacking force is usually implemented using empirical *** should be emphasized that the jacking force will change for each site,depending on the magnitude of overcut,lubricants,work stoppages,geology and misalignment.A particle method is proposed to estimate the jacking force along the *** microparameters are calibrated for sandy soils in Shenyang,so that the macroscale material behavior can be reproduced using the particle ***,the normal force around the pipe circumference can be derived in the particle model,after which the interface friction coefficient is applied to evaluate the friction resistance mobilized at the soil-pipe interface.A modified Protodyakonov’s arch model can be used to assess the magnitude of earth pressure acting on the shield *** the end,the combination of friction resistance and face pressure provides the jacking *** efficacy of the proposed particle method is demonstrated by comparing calculated jacking forces with those measured in the field for three types of jacking machines in sandy soils under the Hun River,Shenyang.

关键词： Pipe jacking Jacking force Particle methods Distinct element

A feasibility study on the design and walking operation of a biped locomotor via dynamic simulation

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Frontiers of Mechanical Engineering 2016年第2期11卷 144-158页

作者： Mingfeng WANG marco CECCARELLI Giuseppe CARBONE School Of Mechanical and Electrical Engineering Central SouthUniversity Changsha 410083 China Laboratory of Robotics andMechatronics (LARM) DICeM University of Cassino and SouthLatium Cassino 03043 Italy Laboratory of Robotics and Mechatronics (LARM) DICeM Universityof Cassino and South Latium Cassino 03043 Italy

A feasibility study on the mechanical design and walking operation of a Cassino biped locomotor is presented in this paper. The biped locomotor consists of two identical 3 degrees-of-freedom tripod leg mechanisms with a parallel manipulator architecture. Planning of the biped walking gait is performed by coordinating the motions of the two leg mechanisms and waist. A three- dimensional model is elaborated in SolidWorks environ- ment in order to characterize a feasible mechanical design. Dynamic simulation is carried out in *** environment with the aims of characterizing and evaluat- ing the dynamic walking design. Simulation results performance of the proposed show that the proposed biped locomotor with proper input motions of linear actuators performs practical and feasible walking on fiat surfaces with limited actuation and reaction forces between its feet and the ground. A preliminary prototype of the biped locomotor is built for the purpose of evaluating the operation performance of the biped walking gait of the proposed locomotor.

关键词： feasibility study biped locomotor bipedwalking mechanical design dynamic simulation tripodleg mechanism 3-UPU parallel manipulator

Determining relative block structure rating for rock erodibility evaluation in the case of non-orthogonal joint sets

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 72-87页

作者： Lamine Boumaiza Ali Saeidi marco Quirion Department of Applied Saences University of Quebec at Chicoutimi Hydro-Quebec

The most commonly used method for assessing the hydraulic erodibility of rock is Annandale's *** method is based on a correlation between the erosive force of flowing water and the capacity of rock resistance. This capacity is evaluated using Kirsten's index, which was initially developed to evaluate the excavatability of earth materials. For rocky material, this index is determined according to certain geomechanical factors related to intact rock and rock mass, such as compressive strength of intact rock, rock block size, discontinuity shear strength and relative block structure. To quantify the relative block structure, Kirsten(1982) developed a mathematical expression that accounts for the shape and orientation of the blocks relative to the direction of flow. Kirsten's initial concept for assessing the relative block structure considers that the geological formation is mainly fractured by two joint sets forming an orthogonally fractured system. An adjusted concept is proposed to determine the relative block structure when the fractured system is non-orthogonal where the angle between the planes of the two joint sets is greater or less than 90°. An analysis of the proposed relative block structure rating shows that considering a non-orthogonally fractured system has a significant effect on Kirsten's index and, as a consequence, on the assessment of the hydraulic erodibility of rock.

关键词： Fractured rock Dip angle Dip direction Joint spacing Relative block structure Hydraulic erodibility of rock Annandale’s method Kirsten’s index

Perianal Crohn's disease: Is there something new?

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World Journal of Gastroenterology 2011年第15期17卷 1939-1946页

作者： Cesare Ruffolo Marilisa Citton marco Scarpa Imerio Angriman marco Massani Ezio Caratozzolo Nicolò Bassi Ⅱ Department of Surgery (IV unit) Regional Hospital Ca' Foncello 31100 Treviso Italy Department of Surgicaland Gastroenterological Sciences University of Padova 35122 Padua Padova Italy Department of Oncological Surgery VenetoOncological Institute 35100 Padova Italy Department of Surgicaland Gastroenterological Sciences University of Padova 35122Padua Padova Italy

Perianal lesions are common in patients with Crohn's disease, and display aggressive behavior in some cases. An accurate diagnosis is necessary for the optimal management of perianal lesions. Treatment of perianal Crohn's disease includes medical and/or surgical options. Recent discoveries in the pathogenesis of this disease have led to advances in medical and surgical therapy with good results. Perianal lesions in Crohn's disease remain a challenging aspect for both gastroenterologists and surgeons and lead to a greatly impaired quality of life for all patients affected by this disease. A multidisciplinary approach is mandatory to obtain the best results.

关键词： Crohn disease Diagnosis Biologic therapy Surgery Rectal fistula

Design and simulation of a cable-pulley-based transmission for artificial ankle joints

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Frontiers of Mechanical Engineering 2016年第2期11卷 170-183页

作者： Huaxin LIU marco CECCARELLI Qiang HUANG Intelligent Robotics Institute School of Mechatronical Engineering Beijing Institute of Technology Beijing 100081 China Key Laboratory of Biomimetic Robots and Systems (Beijing Institute of Technology) Ministry of Education Beijing 100081 China Laboratory of Robotics and Mechatronics (LARM) DICeM University of Cassino and South Latium Cassino 03043 Italy Beijing Innovation Center for Intelligent Robots and Systems Beijing 100081 China State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing 100081 China

In this paper, a mechanical transmission based on cable pulley is proposed for human-like actuation in the artificial ankle joints of human-scale. The anatomy articular characteristics of the human ankle is discussed for proper biomimetic inspiration in designing an accurate, efficient, and robust motion control of artificial ankle joint devices. The design procedure is presented through the inclusion of conceptual considerations and design details for an interactive solution of the transmission system. A mechanical design is elaborated for the ankle joint angular with pitch motion. A multi-body dynamic simulation model is elaborated accordingly and evaluated numerically in the ADAMS environment. Results of the numerical simulations are discussed to evaluate the dynamic performance of the proposed design solution and to investigate the feasibility of the proposed design in future applications for humanoid robots.

关键词： biomimetic designs ankle joints cable-pulleytransmissions multi-body dynamic simulation numericalcharacterization